119 citations · 222 across the 7 of their papers we have counts for
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Mass Enhancement in an Intermediate-Valent Regime of Heavy-Fermion Systems
Katsunori Kubo
We study the mechanism of the mass enhancement in an intermediate-valent regime of heavy-fermion materials. We find that the crossovers between the Kondo, intermediate valent, and…
Variational Monte Carlo study of ferromagnetism in the two-orbital Hubbard model on a square lattice
Katsunori Kubo
To understand effects of orbital degeneracy on magnetism, in particular effects of Hund's rule coupling, we study the two-orbital Hubbard model on a square lattice by a variational…
Ferromagnetism and orbital order in the two-orbital Hubbard model
Katsunori Kubo
We investigate spin and orbital states of the two-orbital Hubbard model on a square lattice by using a variational Monte Carlo method at quarter-filling, i.e., the electron number…
Magnetic Susceptibility of Multiorbital Systems
Katsunori Kubo, Takashi Hotta
Effects of orbital degeneracy on magnetic susceptibility in paramagnetic phases are investigated within a mean-field theory. Under certain crystalline electric fields, the magnetic…
Multipole ordering in f-electron systems
Katsunori Kubo, Takashi Hotta
In order to investigate multipole ordering in f-electron systems from a microscopic viewpoint, we study the so-called Γ_8 models on three kinds of lattices, simple cubic (sc), bcc,…
Analysis of f-p model for octupole ordering in NpO2
Katsunori Kubo, Takashi Hotta
In order to examine the origin of octupole ordering in NpO2, we propose a microscopic model constituted of neptunium 5f and oxygen 2p orbitals. To study multipole ordering, we deri…